This invention relates to an air intake system of a multi-cylinder internal-combustion engine having a connection pipe arranged between opposite resonance containers which communicate with respective cylinders by way of suction pipes, a swivellable throttle valve inserted into an opening in the connection pipe, and a bearing support fastened to the connection pipe closing the opening.
The air intake system of German Patent Document DE-P 43 15 129.9-13, which is not a prior publication, and corresponding U.S. Pat. No. 5,406,913, is a model of an air intake system having an increased mean pressure over the entire rotational speed range. Thus, an increased amount of fresh air is supplied to each cylinder which results in a clear improvement of the volumetric efficiency. In this case, a throttle valve in a connection pipe is switched in a targeted manner between two resonance containers.
It is an object of the present invention to optimize an air intake system having a throttle valve constructively as well as with respect to manufacturing techniques, while maintaining excellent functionality and efficiency.
This object has been achieved according to the present invention by providing in an air intake system having a connection pipe arranged between opposite resonance containers, a swivellable throttle valve which is inserted into the connection pipe through an opening, and a bearing support which is fastened to the connection pipe, closing the opening.
The throttle valve is mounted in the connection pipe, which can be constructed in one piece, in a simple manner using a bearing support. The bearing support, which is constructed as a separate component, has minimal space requirements and can easily be integrated with the above-mentioned connection pipe. The bearing support and the throttle valve form a prefabricated constructional unit which can be installed within the scope of flexible manufacturing processes into the air intake system. A sealing gasket disposed between the bearing support and the connection pipe, as well as between the bearing support and a section supplementing the interior pipe wall of the connection pipe, ensure a gas-tight installation of the bearing support. The design of the bearing support allows the use of different materials, such as plastic or light metal.
To promote laminar flow through the connection pipe, the bearing support may be provided with a section which mirrors the interior of the connection pipe in the area of the opening, serving to reduce transitional surfaces in this area.
These and other objects, features and advantages of the present invention will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings.